JPH0651235A - Laser machining optical system - Google Patents

Abstract

PURPOSE:To prevent an optical fiber and optical lenses from being broken and to achieve simplification and weight reduction of an optical system. CONSTITUTION:An optical fiber 5 is sealed by an O-ring 10 via a coupling 8 and attached to the inlet side portion of a main body 1. Optical lenses 3, 3a are disposed on that side of the main body on which a laser beam 9 from the optical fiber 5 impinges. The optical lenses 3, 3a are held within the main body 1 by a lens holder 14 having taper holes 15 therethrough. An atmospheric gas inlet nozzle 2 is mounted to the inlet side portion of the main body 1. An outlet nozzle 4 from which an outgoing laser beam 9a is emitted is mounted to the outlet side portion of the main body 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air-cooled laser processing optical system for use in a laser processing apparatus, and in particular, when processing with a laser, the laser beam is focused to perform processing.

[0002]

2. Description of the Related Art Laser processing is used for cutting, welding, etc. of an object to be processed. At this time, a plasma gas is supplied to generate plasma for cutting, and an inert gas is supplied to prevent oxidation of the object. Atmosphere gas is supplied to the processed surface according to the purpose of processing such as supply. At this time, the atmospheric gas flows on the downstream side where the gas is injected to the heat treatment section of the laser processing optical system. This example will be described with reference to FIG. 11, which is a sectional view of the laser processing optical system.

That is, as shown in FIG. 11, an atmosphere gas inlet nozzle 2 is connected to the main body 1 from a position where a rear optical lens 3a is provided, and a pair of optical lenses 3 and 3a are provided in the main body 1. It is held via the lens holder 7. An outlet nozzle 4 is connected to the end of the main body 1. An optical fiber 5 is attached to the inlet side of the main body 1 via a coupling 8, and the coupling 8 is fixed with a screw 6. An O-ring is provided between the coupling 8 and the main body 1 at the inlet side.
Sealed with 10.

In the figure, 9 is an incident laser beam and 9a is an emitted laser beam. The atmospheric gas is supplied from the inlet nozzle 2 between the rear optical lens 3a and the outlet nozzle 4, and is blown from the outlet nozzle 4 to the processing section for laser processing.

Further, cooling of the optical system has become a problem with the increase in output of the processing apparatus. That is, energy loss occurs when the incident laser beam 9 passes through the optical fiber 5 or the front optical lens 3, but this becomes thermal energy, and the optical fiber 5 or the optical lenses 3 and 3a and the entire optical system have heat, As a result, the optical fiber 5 and the optical lenses 3 and 3a may be damaged.

In order to prevent this, a water-cooled or air-cooled laser processing optical system is used. This is shown in Figure 12 and
This will be explained using 13. FIG. 12 is a sectional view of the air-cooled laser processing optical system, and FIG. 3 is a sectional view of the water-cooled laser processing optical system. 12 and 13, the same parts as those in FIG. 11 or parts having the same functions are designated by the same reference numerals, and the description of the overlapping parts will be omitted.

That is, in FIG. 12, the inlet nozzle 2 is connected to the end face on the inlet side of the main body 1, and the double pipe 11 is provided inside the main body 1.
The structure is arranged. The atmosphere gas 2 blown into the main body 1 from the inlet nozzle 2 flows in the double pipe 11 as shown by the arrow, and flows out from the outlet nozzle 4. The inside of the main body 1 is cooled by the circulation of the atmospheric gas.

The water-cooled laser processing optical system shown in FIG. 13 is provided with a water chamber 13 on the outer wall of the main body 1, and other parts are shown in FIG.
The structure conforms to 11. In this optical system, water is passed through the water chamber 13, thereby cooling the laser processing optical system.

[0009]

In a laser processing optical system having an atmosphere gas flow path, a hose and a nozzle for horizontally supplying the atmosphere gas are attached to the main body of the laser processing optical system. It is not used for anything other than the shield on the processed surface.

In the air-cooled laser processing optical system, the optical fiber 5
Is not performed, the cooling efficiency for the optical lenses 3 and 3a is low, and the double tube 11 is provided in the main body 1 to structurally increase the size and complexity.

In the water-cooled laser processing optical system, the cooling efficiency for the optical lenses 3 and 3a is high. However, since the water chamber 13 is additionally provided, the laser processing optical system has a water cooling system and an atmosphere gas system. Have a lineage,
There is a problem that the laser processing optical system itself becomes large. That is, since the flow path for the atmospheric gas must be provided separately, there is a problem in that the structure becomes large.

The present invention has been made to solve the above problems, and prevents damage to optical fibers and optical lenses without impairing the original function of atmospheric gas, and simplifies and reduces the weight of optical systems. An object of the present invention is to provide a laser processing optical system that can be realized.

[0013]

According to the present invention, there is provided a main body for entering and emitting laser light, and a coupling for fixing an optical fiber for entering the laser light in the main body to the main body through an O-ring. An optical lens for condensing the laser light emitted from the optical fiber, a lens holder for holding the optical lens, and an atmosphere gas flow path for cooling the optical fiber and the optical lens provided on the lens holder and the main body. And a laser processing optical system.

[0014]

The atmospheric gas flowing into the main body flows around the optical fiber and the front optical lens, passes through the tapered hole of the lens holder, and flows around the rear optical lens. This effectively cools the optical fiber and the optical lens.

Further, by directly blowing the atmospheric gas onto the optical lens, the optical lens is uniformly cooled, which leads to prevention of damage to the optical lens. Further, since the atmosphere gas can be shared with the cooling gas and is the same, the laser processing optical system can be simplified and reduced in weight.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the laser processing optical system according to the present invention will be described with reference to FIGS. 2 is shown in FIG.
FIG. 3 is a cross-sectional view of the main body 1 of FIG. 3, and FIG. 3 is a front view of the lens holder of FIG.

In FIG. 1, reference numeral 1 is a horizontally long cylindrical main body, a large number of grooves 1a are formed on the inner surface of the main body 1 as shown in FIG. 2, and an atmosphere gas inlet nozzle is provided on the inlet side of the main body 1. 2 and an outlet nozzle 4 on the outlet side. In the main body 1, the optical lenses 3 and 3a are attached to the lens holder 14
The lens holder 14 has a tapered hole 15 formed therein. Further, an optical fiber 5 is attached to the entrance side of the main body 1a while being sealed by an O-ring 10 via a coupling 8. A flow path for atmospheric gas is formed between the outer side of the coupling 8 and the inner surface of the main body 1 on the inlet side.

In the above laser processing optical system, the atmospheric gas flows from the inlet nozzle 2 into the main body 1, passes through the plurality of grooves 1a provided on the inner surface of the main body 1, and goes forward from the end position of the optical fiber 5. It is blown onto the optical lens 3.

2 is a sectional view showing the groove 1a in the main body 1, and FIG. 3 is a front view of the lens holder 14 having the tapered hole 15 as seen from the upstream direction of the atmosphere gas flow path. Taper hole 15
Are angled in the direction of the center of the circle of the lens holder 14 and in the circumferential direction. The atmospheric gas passing through the tapered hole 15 of the lens holder 14 swirls toward the center of the circle. That is, the atmospheric gas blown to the front optical lens 3 passes through the tapered hole 15 of the lens holder 14 and is blown to the rear optical lens 3a. Although the number of optical lenses 3 and 3a varies depending on the processing purpose, the atmospheric gas that has passed the target number is finally ejected from the nozzle 4 at the tip of the laser processing optical system. Next, the operation of the above configuration will be described.

Atmospheric gas is blown into the optical lenses 3 and 3a in the main body 1 in a spiral shape, and therefore the optical lenses 3 and 3a.
It is possible to cool the laser transmitting part which is considered to increase the temperature most. In addition, when minute dust is accidentally mixed in the atmospheric gas and adheres to the surfaces of the optical lenses 3 and 3a,
This may serve as a heat generation source and cause damage to the optical lenses 3 and 3a. However, the dust is instantly blown off by the blowing of the atmospheric gas 2, and the damage to the optical lenses 3 and 3a can be prevented. Further, the atmosphere gas blown out from the main body 1 can be shared with the cooling gas, and the type and the flow rate can be selected in accordance with the purpose of processing. Next, FIG. 4 and FIG.
The second embodiment of the present invention will be described below.

In FIG. 4, the part different from the embodiment of FIG. 1 is the main body 17
5 has a ∑-shaped groove 17a formed on the inner surface thereof and a groove 16a formed on the outer peripheral surface of the lens holder 16 as shown in FIG. Since other parts are the same as those in FIG. 1, description of the overlapping parts will be omitted.

FIG. 5 shows a sectional view of the lens holder 16 having the groove 16a. Grooves 16a are cut at a plurality of locations around the lens holder 16, and an atmosphere gas flow path is formed through the grooves 16a. Although the optical lenses 3 and 3a are cooled by the atmosphere gas passing through the groove 16a, the groove 17a of the main body 1 has a great cooling effect because of the structure that serves as a fin.

Further, since the structure is simple, the laser processing optical system can be simplified and lightened. In addition, lens holder
Instead of the 16 grooves 16a, a groove similar to the groove 16a may be formed on the inner surface of the main body 1 to form an atmosphere gas flow path.

FIG. 6 shows another example of the optical lenses 3 and 3a in FIGS. The optical lens 18 shown in FIG. 6 is provided with a plurality of grooves 18a around the optical lens 18 to serve as a flow path for atmospheric gas. With this optical lens 18, as in the first and second embodiments, it is possible to cool the optical lens by the atmospheric gas and to simplify and reduce the weight of the laser processing optical system main body.

FIG. 7 shows only the essential parts of the third embodiment of the present invention. That is, in the third embodiment, the optical fiber end holder 19 having the tapered hole 19a is provided on the inlet side of the main body 1. The other parts are the same as in the above embodiment. FIG. 7 shows a cross section of the optical fiber 5 of the laser processing optical system main body 1 and the vicinity of the coupling 8 that holds the optical fiber 5.

In this third embodiment, the ambient gas cools the coupling 8 as it flows along the groove 16 provided between the coupling 8 and the body 1. At the end of the coupling 8, the atmospheric gas 2 cools the end of the optical fiber 5 which is bent inward.

The bent atmospheric gas is blown to the front optical lens 3 through the hole of the optical fiber end holder 19 having the tapered hole 19a formed so that the gas can easily flow, and the optical fiber 3 is thereby blown. The temperature rise at the end of 5 can be suppressed and the optical fiber 5 can be prevented from being damaged. Next, a fourth embodiment of the present invention will be described with reference to FIG.

The fourth embodiment shows an example in which an atmosphere gas nozzle 20 having a bent blowing hole 20a is attached to the end surface of the main body 1 on the inlet side. Other parts are the same as those in the first embodiment. The atmosphere gas is directly blown to the end portion of the optical fiber 5 from the blowing hole 20a of the atmosphere gas nozzle 20 which is bent toward the end portion of the optical fiber 5. This ensures that the end portion of the optical fiber 5 is cooled.

Next, a fifth embodiment of the present invention will be described with reference to FIG. The fifth embodiment shows an example in which the rectifier 21 is attached to the inner surface of the inlet side end of the main body 1. That is,
As shown in FIG. 9, a circular vertebra rectifier 21 is provided at the end of the optical fiber 5 to concentrate the atmospheric gas and reduce the processing point returning to the optical fiber 5 and the reflected light from the optical lens 3. . This enables indirect cooling as well as direct cooling of the atmospheric gas 2. Next, a sixth embodiment of the present invention will be described with reference to FIG. The sixth embodiment shows an example of a laser processing optical system when the laser beam 9 is bent and used as shown in FIG.

That is, in FIG. 10, the main body 1 is bent into a hook shape, the optical lenses 3 and 3a are arranged in the vertical portion of the main body 1, and the bending mirror 23 is provided at the end of the horizontal portion. Are arranged. The nozzle 22 for flowing the atmospheric gas into the main body 1 is attached to the end surface on the inlet side of the main body 1. The other parts are almost the same as in the first embodiment.

Normally, the bending mirror 23 has heat, so that a water cooling device for the bending mirror 23 is necessary. However, even when the laser beam 9 is bent, the bending mirror 23 can be cooled by the atmospheric gas. Therefore, since a cooling device for the folding mirror 23 is not required, the laser processing optical system can be simplified and reduced in weight.

[0032]

According to the present invention, the optical fiber and the optical lens are cooled by the flow of the atmospheric gas to prevent the optical fiber and the processed lens from being damaged. Further, since the atmospheric gas is used as both the atmospheric gas and the cooling gas, the laser processing optical system can be simplified and reduced in weight without the need for attached equipment such as cooling water.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a laser processing optical system according to the present invention.

FIG. 2 is a vertical cross-sectional view showing a laser processing optical system main body in FIG.

FIG. 3 is a front view showing a lens holder with a tapered hole in FIG.

FIG. 4 is a vertical sectional view showing a second embodiment of the laser processing optical system according to the present invention.

5 is a front view showing the grooved lens holder in FIG. 4. FIG.

FIG. 6 is a front view showing another example of the optical lens in FIGS. 1 and 4.

FIG. 7 is a sectional view showing an essential part of a third embodiment of the laser processing optical system according to the present invention.

FIG. 8 is a sectional view showing an essential part of a fourth embodiment of a laser processing optical system according to the present invention.

FIG. 9 is a sectional view showing a main part of a fifth embodiment of a laser processing optical system according to the present invention.

FIG. 10 is a sectional view showing an essential part of a sixth embodiment of the laser processing optical system according to the present invention.

FIG. 11 is a vertical cross-sectional view showing a conventional processing optical system.

FIG. 12 is a vertical sectional view showing a conventional air-cooled laser processing optical system.

FIG. 13 is a vertical cross-sectional view showing a conventional water-cooled laser processing optical system.

[Explanation of symbols]

1 ... Laser processing optical system main body, 2 ... Inlet nozzle, 3, 3a
… Optical lens, 4… Exit nozzle, 5… Optical fiber, 6…
Screws, 7 ... Lens holder, 8 ... Coupling, 9 ... Incident laser light, 9a ... Emitted laser light, 10 ... O-ring, 11 ... Double pipe, 12 ... Cooling water, 13 ... Water chamber, 14 ... Lens holder, 15 ...
Tapered hole, 16 ... Lens holder, 17 ... Main body, 18 ... Optical lens, 19 ... Optical fiber end holder, 20 ... Atmosphere gas nozzle, 21 ... Rectifier, 22 ... Nozzle, 23 ... Bending mirror.

Claims (1)

[Claims] 1. A body for entering and emitting laser light,
A coupling for fixing an optical fiber for injecting the laser light into the main body via an O-ring in the main body, an optical lens for condensing the laser light emitted from the optical fiber, and a lens for holding the optical lens. A laser processing optical system comprising: a holder; and an atmosphere gas flow path for cooling the optical fiber and the optical lens provided on the lens holder and the main body.